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Kidnocker: Blazing palo verdes light up area
Each year we discuss the palo verde tree, but each year at this time it draws our eye with its spectacular bloom. The bright light across the Santa Cruz Valley is in large part because of these thousands of trees, big and little, all aflame with yellow flowers.
Representing some of the most drought-tolerant trees in our desert, these native trees are quite prolific and so appear to be everywhere especially each spring. The trees themselves are barely visible because of their dense lemon-yellow blossoms. Masses of the small pea-like flowers are literally drenching the trees.
Palo verdes (cercidium) are legumes, or seedpod producing plants. Because of their ability to withstand extreme heat and intense sun, they are found throughout the Sonoran and Mohave deserts. They are also known for their smooth green bark. The name palo verde translated from Spanish means “green stick.”
One of the more common in this family, the blue palo verde (cercidium floridum) is so called because its bark is blue-green. Others of the species have yellow-green bark. The blue palo verde blooms on leafless branches, and only after summer rains do the small leaves appear.
The balance of the year blue-green branches and twigs substitute for leaves by producing the sugars necessary for survival. Also without the exposed leaf surfaces, the interior water supply is not so quickly evaporated. This is another prime example of how a native plant has adapted to harsh life in the desert.
Although leafless much of the year, the blue palo verde appears to be evergreen because of its dense, spiny twigs and branches. After ripening in early summer, the seedpods that follow the flowers often hang onto the tree for months. For generations, Native Americans ground the seed and prepared the pods and seeds as cooked vegetables.
The blue palo verde tree grows moderately fast and can get to 30 feet high with a 30-foot spread.
If you are considering including this tree in your landscape, first make certain you have the space. With an overall rounded form, it also wants to send its lower branches toward the ground. Therefore, to prevent a weeping form, a little trimming may be necessary to provide an overhead canopy.
The foothills palo verde (C. microphyllum) is a bit smaller with a 10- to 20-foot height and equal spread. It also grows slower. It has yellow-green bark, and the buttery-yellow flowers appear later than those of the blue palo verde.
This palo verde is often found on rocky slopes and gravelly flats throughout our area. Its seeds are a staple of rodents that bury them for safekeeping. When the monsoons arrive, the uneaten seeds will abundantly germinate, though only a few will survive.
Up to three-fourths of the food manufactured by the foothills palo verde is made by the bark. The balance is produced by the small leaves which may come and go often in response to rain or drought. Because bark photosynthesis is so inefficient, these trees grow slowly on the low food production provided.
There are a number of other varieties of palo verde trees available. One that has become quite popular in recent years is the “desert museum.” This is a hybrid that is beloved by professional landscapers because it is a fast grower, and usually matures at about 18 feet high.
Flowers remain viable on the desert museum for a longer period than other palo verdes. Originating at the Arizona-Sonora Desert Museum, this hybrid was formerly difficult to find. It is now readily available at most nurseries and garden centers.
All young palo verdes benefit from supplemental water every month or two. Once established (after about 2 years) they will survive on rainfall. As with most plants, they fare better if given a good soaking during extended hot, dry spells. Most in cultivation are not susceptible to pests or diseases. Their light shade provides a perfect spot for growing perennials and succulents.
Because of their heavy bloom, palo verde trees do create noticeable yellow litter around the yard. If you do not care for the yellow carpet, the small flowers are easily vacuumed.
The native blue palo verde was named the official Arizona state tree in 1954. Enjoy these majestic yet durable desert trees that are currently painting the Santa Cruz Valley in tones of yellow!
Mary Kidnocker is a Master Gardener who writes from a local perspective. Her columns are featured each Sunday.
Representing some of the most drought-tolerant trees in our desert, these native trees are quite prolific and so appear to be everywhere especially each spring. The trees themselves are barely visible because of their dense lemon-yellow blossoms. Masses of the small pea-like flowers are literally drenching the trees.
Palo verdes (cercidium) are legumes, or seedpod producing plants. Because of their ability to withstand extreme heat and intense sun, they are found throughout the Sonoran and Mohave deserts. They are also known for their smooth green bark. The name palo verde translated from Spanish means “green stick.”
One of the more common in this family, the blue palo verde (cercidium floridum) is so called because its bark is blue-green. Others of the species have yellow-green bark. The blue palo verde blooms on leafless branches, and only after summer rains do the small leaves appear.
The balance of the year blue-green branches and twigs substitute for leaves by producing the sugars necessary for survival. Also without the exposed leaf surfaces, the interior water supply is not so quickly evaporated. This is another prime example of how a native plant has adapted to harsh life in the desert.
Although leafless much of the year, the blue palo verde appears to be evergreen because of its dense, spiny twigs and branches. After ripening in early summer, the seedpods that follow the flowers often hang onto the tree for months. For generations, Native Americans ground the seed and prepared the pods and seeds as cooked vegetables.
The blue palo verde tree grows moderately fast and can get to 30 feet high with a 30-foot spread.
If you are considering including this tree in your landscape, first make certain you have the space. With an overall rounded form, it also wants to send its lower branches toward the ground. Therefore, to prevent a weeping form, a little trimming may be necessary to provide an overhead canopy.
The foothills palo verde (C. microphyllum) is a bit smaller with a 10- to 20-foot height and equal spread. It also grows slower. It has yellow-green bark, and the buttery-yellow flowers appear later than those of the blue palo verde.
This palo verde is often found on rocky slopes and gravelly flats throughout our area. Its seeds are a staple of rodents that bury them for safekeeping. When the monsoons arrive, the uneaten seeds will abundantly germinate, though only a few will survive.
Up to three-fourths of the food manufactured by the foothills palo verde is made by the bark. The balance is produced by the small leaves which may come and go often in response to rain or drought. Because bark photosynthesis is so inefficient, these trees grow slowly on the low food production provided.
There are a number of other varieties of palo verde trees available. One that has become quite popular in recent years is the “desert museum.” This is a hybrid that is beloved by professional landscapers because it is a fast grower, and usually matures at about 18 feet high.
Flowers remain viable on the desert museum for a longer period than other palo verdes. Originating at the Arizona-Sonora Desert Museum, this hybrid was formerly difficult to find. It is now readily available at most nurseries and garden centers.
All young palo verdes benefit from supplemental water every month or two. Once established (after about 2 years) they will survive on rainfall. As with most plants, they fare better if given a good soaking during extended hot, dry spells. Most in cultivation are not susceptible to pests or diseases. Their light shade provides a perfect spot for growing perennials and succulents.
Because of their heavy bloom, palo verde trees do create noticeable yellow litter around the yard. If you do not care for the yellow carpet, the small flowers are easily vacuumed.
The native blue palo verde was named the official Arizona state tree in 1954. Enjoy these majestic yet durable desert trees that are currently painting the Santa Cruz Valley in tones of yellow!
Mary Kidnocker is a Master Gardener who writes from a local perspective. Her columns are featured each Sunday.
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